An R/C helicopter rotates a main rotor blade that is applied with an angle of attack and generates lifting force, changes the angle of attack of the main rotor blade through a link mechanism from a swash plate mounted to a base portion of a mainmast, and inclines a rotation surface of a rotor using the change in the lifting force to generate thrust force in an inclined direction, thereby flying.
As a method that controls a pitch angle of the main rotor blade, a Bell type that directly inclines the main rotor blade through the link mechanism from the swash plate and a Hiller type that inclines a stabilizer blade through the link mechanism from the swash plate, transmits a balance change in the lifting force generated by inclining the stabilizer blade to the main rotor blade, and changes the pitch angle are used. In the R/C helicopter, since excellent steering responsiveness is obtained by control of a Bell-Hiller type corresponding to a combination of the Bell type and the Hiller type, the Bell-Hiller type is widely used in general (for example, refer to Patent Documents 1 and 2).
The reason why the rotation surface of the main rotor is controlled to be inclined in the same direction as the swash plate by the inclining operation of the swash plate is as follows. If force is applied to a rotating object, a gyro precession where an effect of the force appears in a progress direction of a rotation of 90 degrees acts. In order to cause the main rotor and the stabilizer to control external stress applied to an airframe by an effect of the gyro precession and stabilize the flying operation, in the R/C helicopter of the Bell-Hiller type, a phase difference of an output with respect to an operation input is set as 90 degrees, and the stabilizer and the main rotor are disposed in directions orthogonal to each other.
[Patent Document 1] Japanese Utility Model Application No. H6-7751
[Patent Document 2] Japanese Patent Application Laid-Open No. 2003-103066